You won’t get electric tanks for the same reason you won’t get electric planes: energy density and supply chains.

An Abrams has a multi-fuel jet turbine that’ll take diesel, gas, and jet fuel; all of which are easy to transport and store in bulk, in any environment, compared to needing to generate and store the same quantity of energy.

The closest tanks will come any time soon is a diesel-electric hybrid, for noise and electric load purposes (EW, lasers, etc).